1. Field of the Invention
This invention relates to automatic inflators for inflatable articles such as life rafts, life vests, and the like. More particularly, this invention relates to inflators that are actuated automatically upon immersion in water.
2. Description of the Background Art
Presently, there exists many types of inflators designed to inflate inflatable articles such as personal floatation devices (life vests, rings and horseshoes), life rafts, buoys and emergency signaling equipment. Manual inflators typically comprise a body for receiving the neck of a cartridge of compressed gas such as carbon dioxide. A reciprocating piercing pin is disposed within the body of the inflator for piercing the frangible seal of the cartridge to permit compressed gas therein to flow into a manifold assembly of the inflator and then into the article to be inflated. Typically, a manually movable firing lever is operatively connected to the piercing pin such that the piercing pin pierces the frangible seal of the gas cartridge upon jerking of a ball lanyard. U.S. Pat. No. 3,809,288, the disclosure of which is hereby incorporated by reference herein, illustrates one particular embodiment of a manual inflator.
While manual inflators work suitably well, it was quickly learned that in an emergency situation, the person needing the assistance of the inflatable device, such as a downed aviator, injured person, or a man overboard, would fail or be unable to manually activate the inflator. Accordingly, it was realized that a means should be provided for automatically activating the inflator in such an emergency situation.
In response to this realized inadequacy of the prior art manual inflators, water-activated automatic inflators were developed which, when exposed to a fluid such as water, automatically activated the piercing pin of the inflator when immersed in water thereby causing inflation of the inflatable device. Typical water-activated automatic inflators comprise a water activated trigger assembly including a water destructible or dissolvable element, often referred to as a “bobbin”, which retains a spring-loaded actuator pin in a cocked position in alignment with a piercing pin. Upon exposure to water, the “pill” contained within the bobbin immediately starts dissolving and then destructs altogether once it loses sufficient rigidity and therefore the bobbin loses its ability to hold-back the spring-loaded actuator pin in its cocked position. The spring-loaded actuator pin is thus released to forcibly move from its cocked position to an actuated position to strike the piercing pin, either directly or indirectly by means of an intermediate transfer pin. Upon striking the piercing pin, the pin fractures the seal of the cartridge thereby allowing the gas contained therein to flow into the inflatable device to inflate the same. Representative automatic actuators for inflators are disclosed in U.S. Pat. Nos. 3,059,814, 3,091,782, 3,426,942, 3,579,964, 3,702,014, 3,757,371, 3,910,457, 3,997,079, 4,223,805, 4,267,944, 4,260,075, 4,382,231, 4,436,159, 4,513,248, 4,627,823, 5,076,468, 5,601,124, 5,685,455, 5,562,233, 5,370,567, 5,333,756, 4,488,546 and 5,694,986, the disclosures of which are hereby incorporated by reference herein.
While the above referenced automatic inflators operate quite well in inflating inflatable devices in the event of an emergency situation, one major disadvantage to these automatic inflators is the tendency of their bobbins to prematurely destruct in non-emergency situations by exposure of the pill contained therein to excessive humidity. Bobbin pills of various designs and chemical compositions have been used to minimize their susceptibility to humidity. Indeed, the problem of premature and unintentional activation of automatic inflators is so acute that it is not uncommon for the water-destructible bobbins of the automatic inflators to be replaced on a regular basis as part of a periodic maintenance program, particularly when the inflators are employed in humid weather conditions or around water. In this regard, it is noted that each of the prior art water-activated automatic inflators disclosed in the above referenced patents teach a structure which may easily be disassembled to facilitate the replacement of the water destructible bobbin so that the inflator may be periodically maintained by replacing the bobbin. In order to minimize such periodic maintenance, there therefore exists a need for an improved bobbin pill that is less susceptible to humid weather conditions and yet retains its ability to immediately dissolve upon being immersed in water.
Therefore, it is an object of this invention to provide an improvement which overcomes the aforementioned inadequacies of the prior art devices and provides an improvement which is a significant contribution to the advancement of the inflation art.
Another object of this invention is to provide an improved bobbin pill design for an automatic inflator that is less susceptible to humid weather conditions that may prematurely activate the automatic inflator in non-emergency situations.
Another object of this invention is to provide an improved bobbin pill design for an automatic inflator that provides sufficient strength to retain the actuator pin in its cocked position and thereby minimize premature activation of the automatic inflator in non-emergency situations.
Another object of this invention is to provide an improved bobbin pill design for a bobbin of an automatic inflator that comprises at least one surface having an undulating configuration having an increased strength to hold-back the spring-loaded actuator pin and an increased surface area to facilitate dissolving once exposed to water to thereby be less susceptible to humid weather conditions that may otherwise result in the premature activation of the automatic inflator in non-emergency situations.
Another object of this invention is to provide an improved bobbin pill design for an automatic inflator that comprises a surface having an undulating configuration applied to opposing surfaces of the bobbin pill, with the opposing undulations being aligned with respect to each other to maximize the increased strength to hold-back the spring-loaded actuator pin while still being capable of easily dissolving once exposed to water to thereby be less susceptible to humid weather conditions that may otherwise result in the premature activation of the automatic inflator in non-emergency situations.
Another object of this invention is to provide an improved bobbin pill design of various shapes such as annular-shaped (flat and dome-configured) with a center hole, disk-shaped without a center hole, cylindrical-shaped, etc. for use with the respective style of automatic inflator, each such pill shape including an undulating surface configuration that increases the strength to hold-back the spring-loaded actuator pin while still being capable of easily dissolving once exposed to water to thereby be less susceptible to humid weather conditions that may otherwise result in the premature activation of the automatic inflator in non-emergency situations.
Another object of this invention is to provide an improved bobbin pill design for an automatic inflator that comprises non-uniform thickness having an increased strength to hold-back the spring-loaded actuator pin yet still being easily dissolvable once exposed to water to thereby be less susceptible to humid weather conditions that may otherwise result in the premature activation of the automatic inflator in non-emergency situations.
Another object of this invention is to provide an improved bobbin pill design of various shapes such as annular-shaped (flat and dome-configured) with a center hole, disk-shaped without a center hole, cylindrical-shaped, etc. for use with the respective style of automatic inflator, each such shape including a non-uniform thickness that increases the strength to hold-back the spring-loaded actuator pin while still being capable of easily dissolving once exposed to water.
These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or by modifying the invention within the scope of the disclosure. Accordingly, other objects and a more comprehensive understanding of the invention may be obtained by referring to the summary of the invention, and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.